Concept: what if you could, in your fancy terminal, in the year of our
lord 2025, just click on the attrs you're looking at to go to where
they're defined. Currently we only expose this info as
builtins.unsafeGetAttrPos, which is inconvenient as it's not
discoverable to users.
By putting it in this more visible yet invisible spot, it's more likely
to be more useful to more people.
In the current state, this is not the most useful ever due to stuff like
https://github.com/neovim/neovim/discussions/35097. However, it can be
expanded by perhaps adding something like the url format setting ripgrep
has.
Change-Id: I3947f97d5c2056d59099af468d7b855486438227